Actually, they're not. I have a brother in law who was a certified FAA airframe and power plant inspector for a number of years at American. He's been inside and outside of both. His famous quote is "Where Boeing uses rivets and glue, Airbus uses only glue" (Those of you in the assembly industry knows what glue means)
If you heard the stories he told me (from a neutral perspective, he's not vested in either company) you'd fly Boeing only too.
I did.
I am not talking about the structures Rip. The pressure vessel, wings, tail etc are all over built. They have to be so the airplane has a reasonable service life.
It's the systems - avionics, hydraulics, electrics, flaps, flight controls that could be far better built on both manufacturer's airplanes. (forgive the choice of example but google "rudder hard over" accidents).
Respectfully
Rick